I have heard of wax melts that you can use on a ceramic piece.  But if you do not want to go that route, I found this interesting project from Wholesale Supplies Plus called Black Cherry Merlot Wickless Candle Melt. This is a great and safe way to enjoy candles without lighting a wick. You can place this 4 oz tin on a coffee or candle melter,  As the the wax slowly melts, it will fill your room with a wonderful scent of Black Cherry Merlot.